Providing electrical power onboard a helicopter, particularly to helicopter rotor blades for deicing, has traditionally required the use of gearbox mounted generators, located remotely from the rotor blades, which transmit electrical power to the rotor blades through slip rings, as shown in FIG. 1. These power generation devices typically suffer from low efficiency and may require frequent maintenance. Accordingly, there is a need for an improved onboard generator for generating electrical power on an aircraft. In particular, there is a need for an improved onboard generator for generating electrical power for rotor blade deicing on a helicopter. Embodiments of the present invention may meet this need by providing a mast-mounted generator which may eliminate the necessity for slip rings by generating the usable power at or near the site of use, i.e., at or near the rotor blades. Some embodiments of the present invention may further incorporate an optional counter-rotating stator in the generator.